View Single Post
Oct4-06, 02:48 PM
P: 163

The drawing shows a large cube(mass=25 kg) being accelerated accross a frictionless surface by a horizontal force P. A small cube(mass=4.0 kg) is in contact with the front surface of the large cube and will slide down unless P is sufficiently large. The coefficient of static friction between the cubes in 0.71. WHat is the smallest magnitude that P can have in order to keep the small cube from sliding downward?

What i did:

4.0 x 9.8 = 39.2 x 0.71 = 27.832 N
39.2 - 27.832 = 4.0a
a = 2.842 m/s/s

I do not know what the acceleration in the x direction must be in order to make the acceleration upward match 2.842.
Phys.Org News Partner Science news on
Bees able to spot which flowers offer best rewards before landing
Classic Lewis Carroll character inspires new ecological model
When cooperation counts: Researchers find sperm benefit from grouping together in mice